Skywriting with a plurality of airplanes



March 28, 1944.

sxY WRITING WITH A PLURALITY oF AIRPLANES 3 Sheets-Sheet 1 Filed Nov. '7, 1940 Jan 271291,29

MTF@

J. T. REMEY, 2,345,152

March 2s, 1944. f 1. T. REMEY 2,345,152

SKY WRITING WITH A PLURALITY OF AIRPLANES Filed Nv; '7, 1940 s sheets-sheet 2' March 28, 1944.

Filed Nov". 7, 1940 J. T. REMEY SKY WRITING WITH A PLURALITY OF AIRPLANES 5 Sheets-Sheet 3 Patented Mar. 28, 1944 UNITED.` STATES PATENT OFFICE I -s'KYWnI'rINGWITHA YLI'JR'ALITY0F5 John Reiney, ew York, N. Y.

appiie'stinn November v, i940, serial No, 364,747 Y 1s oiaims. .gordo-127.1)

This invention is 4a method of andapparatus for forming letters'or symbols in the air by means of contiguous and substantially parallel smoke trails.

In my prior PatentNo. 1,716,794, dated Junev 11, 1929, there is disclosed a method of and apparatus for forming letters or symbols in the air by means of contiguous and substantially parallel smoke trails, and the present invention is an improvement over the method. and apparatus set forth in that patent. f

In my prior patent there isdisclosed a column carrying smoke forming material, which column is carried through the air, in nearly vertical position, by beingsuspended from a moving aircraft. This column is provided with a nl'irnber of smoke-emitting valves, the openingand closingof which are controlledso that the length vsignals* are selectively received, that is, are reand placement of the several smoke trials is such as to build up a letter or symbol.

In the present invention,1 a similarlprinciple is utilized, in that a. pluralityof smoke emitting valves is provided, but in Athis case each valve together with corresponding smoke forming' mechanism, is carried by an individual `airplane and these airplanes fly in contiguous and parallel paths, the valve in each plane being operated so as to control the placement and length of smoke trail formed by that plane. I

The several planes, say ten ,or fteen, in number for example, fly in formation. This may be company front formation, in horizontal. or vertical planes, or in echelon formation, in horizontal, vertical or diagonal front formation.

The` several planes are not mechanically connected. Each plane, however, is providedwith -controllable means for formingat least one heavy smoke trail, andwith means for starting and stopping the smoke trail as desired.

- It will be evident, in order that the several 'K smoke trails emitted by the several planes shall cooperate to form a finished letter, that .the starting and stopping vmechanism in the lseveral planes be very closely and'accurately coordinated and controlled. l

The term smoke is useolherein to cover not only products of combustion, butalsoto cover smoke-like material formed in other ways. The ,smoke may be formed by injectingvoil into the exhaust of the plane, orby a Aspray of titanium tetrachloride, which hydrolyzes on coming into contactwith the moisture in the airand makes a white cloud, or by mixing sprays of ammonia and 'hydrochloric acid, or in any other suitable ,v-

Way.

The principal object, therefore, of this inven- `tion, is to provide a plurality of airplanes, each of which is provided with smoke trail forming mechanism, with coordinated control so that this mechanism in the several planes will be operated, either automatically or manually, to control the length and placement of the smoke trails so as to build up finished letters.

, To accomplishv these objects, individual or selective signals are sent to each airplane and these 'ceived only by the plane for which they are intended, and are amplied. The amplified signal in each case may directly control a smoke valve for starting and stopping the smoke trail. The smoketrail will therefore be placed in the air vand will be of al length depending on the time andnduration of` the signal sent to each plane.

' This control is automatic.

' As a corollary to the automatic operation, manual operation maybe used as follows:

The signalfor an individual plane is received and amplified by that plane as before; however, the amplified signal, instead of directly operating a smoke valve, operates a' signal such as a vlight' or a'rbuzzer, or a tactile device, and as soon as the operator perceives 'such a signal he turns on'the smoke valve and asV soon as the signal stops he turns it off. Slight delays might be involved-in such manual yoperation due to different reaction times of the operators in the several ships, but such variations in reaction times 'would only be a matter of a fractio-n of a second and somuch differences are not serious.

In accordance with the present invention, signal waves sent from the ground or from anotherv airplane are selectively received by the several airplanes and the received Wave is arnplied to work the smoke valve directly or to give a signal to theoperator who, in turn, works `th`e smoke valve. Also, the received wave may be perceived directly by the operator, who works the smoke valve; A` `In my companion application Serial No. 364,748, filed of even date herewith, waves sent from the ground or from'another air- -plane, are received and amplified and caused to vention, for automatic operation.

Figure 3 is a diagrammatic View of actuating l means for the transmitters; Figure 3A is a diagrammaticsideeviewtoillus trate certain features of Figure 3j' l transmitter;

Figure 5 is a diagrammatic view- `lof a radio receiver and cooperating mechanism for" operatl ing a smoke valve; 'i

Figure 6 is a diagrammatic view .of transmitters; j

Figure 7 is a diagrammatic view ,of]a ,sound receiver and cooperating mechanism for yoperating a smoke valve;

Figure 8 is a view of `a, light ktransmitter;

Figure 9 is a view of a light -receiverand .cooperating mechanism for*.operating va smoke valve; ,I

Figure 10 is a view, analogous to 1191112.12., illustrating the relationship ioi" lthe seyerlalde vices of the invention, for manual' operation;

Figure 1l is a view of a light signal, for precep tion by the operator;

Figure 12 is a View 0f `afsdund signal, for perception by the operator.

Referring now to these drawings, in which-similar reference charactersr 'refer-to similar',A parts, a plurality of planes 2,are.shOW,rl in Fi'gure ,1, flying in company front,iorm'ation'.4 'They are here shown as living lina ,horizontal plane, b ut they could fly ina vertical plane, or alongia diagonal, if preferred. lThe vseveral..pla-nesfly in contiguous and substantially parallellpaths.and

ai ,sound emit smoke trails 4, the ,lengthfand' placement of which are controlled so ,that .thetrailscOOperate to build up a finishedA letter or .symbol.

The length and placement .of .thesmoke trails is, in one embodiment of the inventioncontrolled automatically, by radiowaves or by sound way-es or-.by light waves. Each of .these .types ofwaves has individual characteristics,asfto means lfor generating them, wave length, frequency; speed of travel and means .for receiving them, .and therefore are not to be regardedas equivalents.

Referring to Figure 2,-a plurality ,oftransmitters 6, is provided, one .for each ofthe gplanese2. In place of plural transmitters, `afsingle trans.- mitter sending out separate :frequencies-,tope picked up by correspondingly tuned receivers could be used. The transmitters -mayvbe -on :the ground, or in a control plane whichzmay' belflying along with the others and which might be one of the smoke emitting, trail forming planes, or these transmitters might be in a plane Yflying at some distance from the others. Each --of these several transmitterssends vout a signal Awave which is intended for reception only by-a particular plane. The signalsare 'therefore selec-V tive. Each plane is provided'with a receiver 8 which receives the signal intended vfor it, and this receiver in turn is connected to operate a valve l, which when open,^releases a smoke trail, the lengtnand placement of -whicndepends on .15 Figure 4 is a diagrammatic vieWof `a .radio the duration and timing of the received signal wave.

Where a radio signal Wave is used, the transmitter 6 may be a transmitter such as is shown 5 in Figure 4. This transmitter circuit is known and is shown here for the purpose of illustration only, as other known types of radio transmitters may be used. This transmitter 6 uses what is known as a 10 Tri-tet circuit, and `comprises a vacuum or amplifying tube l2, of the6L6 type. The radio frequency choke I4 is about 2.5 mh. A grid leak shown at l5. A screen voltage divider is shown fat-I-6, the B4 battery at I8. I9 is a small dial f glight. The output of the plate circuit is impressed on the usual antenna 20. Such a circuit may havean output of about 10 watts.

, Signal .w.aveof a particular frequency sent -out Iby a Aparticular transmitter 6 is received by 120 the :receiver tuned to that frequency.

.Assuming .there ,are .nine .airplanes for ;a par- 1 ticular :sky Writing ,rieb .and ,that .there yis .an -individual transmitter 4li4 `for sending out. a radio Vwave of a particular frequency, it is necessary to control thetiming and Yduration vof each radio wave inorder to control .the placement and length of the smoke-trail.

This ,may conveniently be done by .the use of `a record12|, Fi g. 3, analogous .to the ,record used 430 k.ina player piano, in that `such .a record may be o'f paper and is provided withindicia in the .form r4ofslots 22,.the ,positloningand length ,of which en .the record determines .the placement and .duration of the .several smoke trails. Ir nine v planes .are used, the record ,is provided with nine `longitudinally extending .channels o r zones, 22', oneforeach plane. 'There xwillalso be provided anelectrical contact making, resiliently mounted y.brush 2,3 .for each of saidchannelsandeach brush 40 23 will 'be connectedto .one of `the two loperating contacts 24 onthe nine transmitters 6, by means of wires 25.

The other contact 24of each transmitterwill be connected by wires28 to a source .of power 30, the other .terminalof whichis ,connected toa common contact ,platepr `cylinder 32 Aon the vunderside `of nthe paper vrecord just below vthe `brushes 23.

The record 2l will be'driven by ,some `constant y speed drive, such as clock work ,or aspring motor,

as in a phonograph, or by .a geared-.down synchronous motor.

Instead of a slotted record, the record could be a lbelt carrying other indicia serving as conv tact-closing devices,` asis Well ,understood in the art ofelectric signs,.s11ch,f forexample, as vmetalflic letters, whichwhen they contact' thebrushes A23,-close corresponding circuits.

"'Fromthe mechanism as above described, itis evident that as 'the recordmoves alongunder the :brushes 23 'the brushes will drop through the slots in the record into contact with cylinder 32 andclosecrcuits to the severaltransmitting sets, ata time, and for alength .of timadepending upon the position and length of the slots.

Each plane is provided with a receiver 8, illustrated diagrammatically in Fig. 5. This is a known ltype of receiver -andis merely shown here as an illustration of .one vconvenient circuit for this purpose. Each receiver is,.of course, tuned to a particular wave length corresponding-to the Wave length of its corresponding transmitter 6. The incoming wave is impressed on and .amplined by a receiving circuit, the amplified .signal (5 operating the relay 34. The relay circuit in:

through a pipe 42, the plane being provided with r any of the known types of smoke forming mechanism.

From the parts as thus described, it will be evident that as the record 2l is fed along under the brushes 23, radio waves will be sent at predetermined times and for predetermined lengths of time as determined by the location and length of the slots 22 in the record, and smoke trails will be formed in the air in exactly the same relationship as to timing and length as exists between the several slots 22 in the paper record.

- Instead of radio waves, sound waves may be used. Due to the relatively slow speed of travel of sound, the planes furthest from the source would receive their sound signals a little late, but this can be readily compensated for by a corresponding change in position of the slots 22 in the control record 2|.

Where a sound wave is used, the record 2| and cooperating brushes are used as before, the brushes and source of power being connected respectively to the terminals 24' of a corren sponding series of sound transmitters, of the type shown in Fig. 6. This sound transmitter is of a known type and comprises a vacuum tube oscillator 4B, the output side of which is connected to a loud speaker or similar sound Waves producing device 4S to produce a sound wave of particular frequency.

Each plane is provided with a sound receiving and amplifying circuit, one type of which is shown in Fig. '7, tuned to respond only to a sound wave of a particular frequency. The incoming sound wave is picked up by the microphone d8, and a corresponding current is impressed on the transformer 50 and thence on the rst stage of a two stage amplier, including a vacuum tube 52 and cooperating parts, the output of which is impressed on the second stage of the amplifier, including a vacuum tube 54 and cooperating parts. The output of the second stage serves to operate a relay 34' analogous to the relay 34 of Figure 5. The relay circuit includes a source of power 36' and a solenoid 38 connected to the handle 40 of a smoke valve 4i in a smoke pipe 42'.

When a sound wave of a particular frequency is received by the receiver, the smoke valve 4I will be opened to produce a smoke trail the length and placement of which is determined by the timing and duration of the received sound wave, which in turn is controlled by the placement and length of the appropriate slots 22 in the rece ord 2l.

Thev smoke trail formation can also be controlled by invisible light Waves, such as infrared or ultra-violet waves. Referring to Fig. 8 a plurality of sources 56 of invisible light rays is provided, each connected to terminals 2t analagous to the terminals 24 and 24' already described, so that the formation of a plurality of bands of invisible light rays of various wave lengths are sent out from 55, through suitable filters 58 as may be desirable. The use of different kinds of invisible light sources and the use of filters will give the necessary different types of light rays to be received individually by the several planes.

Each plane is provided with a light ray receiving apparatus diagrammatically shown in Fig. 9, comprising a photo-electric cell 60 responsive only to a, particular band of invisible light. The output from this cell is impressed on the vacuum tube 62 and amplified to actuate a relay 34", which is connected to operate a relay circuit comprising a source of power 36, to operate a solenoid 38" Which in turn operates the handle 40" of a smoke valve 4i" in a smoke pipe 42".

With the three types of waves thus far described, the formation of smoke trails is entirely automatic, that is to say is entirely independent of the pilot or operator in each plane. However, practically the same mechanism can be used in connection with manual operation of the smoke valves. Referring to Fig. l0, a plurality of transmitters 6 would be provided which would send out radio, sound or light Awaves as before. These waves would be received and amplified by the respective receivers 8 in the diierent planes and these amplified waves would each operate a signal 64 which is perceived by the operator who then operates the handle Ml of control valve 4i to release a smoke trail in accordance with the length and duration of the received signal.

In Fig. ll, the relay 34a, analogous to the relay 34 of Fig. 5, closes a circuit through a battery 66 and light 68. As soon as the operator sees the light 68, he turns on the smoke, and when light 68 is extinguished, he turns it o.

Referring to Fig. l2, the relay 34a closes a circuit through a source of power 66 and a buzzer 10. When the buzzer starts, the operator opcrates valve 4l to turn on the smoke, and when the buzzer stops he turns or the smoke. A tactile signal could evidently be used in place of light t3 or buzzer 1G, if desired.

There is thus provided control means for building up a letter or symbol by means of contiguous and substantially parallel smoke trails, and Where, by either automatic or manual means, the placement and length of the several smoke trails is controlled by the timing and duration of selectively received waves which may be either radio, sound, or light, which waves may be sent from the ground or from an airplane.

While the present preferred embodiments of the invention have been illustrated in some ldetail, it should be understood that the disclosure is illustrative of the invention, and not restrictive thereof, and that it can be carried out in other Ways.

I claim as my invention:

l. The method for forming letters or symbols in the air by means of smoke trails, comprising the steps of assigning to each of a plurality of airplanes a certain part of each letter or symbol, flying said airplanes in contiguous and substantially parallel paths, releasing substantially parallel smoke trails from said airplanes, and controlling the timing, length and placement of the smoke trails by signals to the several airplanes, said smoke trails cooperating to form individual and successive letters or symbols.

2. The method for forming letters or symbols in the air by means of smoke trails, comprising the steps of assigning to each of a plurality of airplanes a certain part of each letter or symbol, flying said airplanes in contiguous and substantially parallel paths, releasing substantially parallel smoke trails from said airplanes, and controlling the timing, length and placement of the smoke trails by signals to the several airplanes,

which signals are perceived by the pilot of the airplane and guide him in operating smoke trail releasingmechanism, said smoke trails cooperating to form individual and successive letters or symbols.

3. The method for forming letters or symbols in the air by means of smoke trails, comprising the steps of assigning to each of a plurality of airplanes a certain part of each letter or symbol, plying said airplanes in contiguous and substantially parallel paths, releasing substantially parallel smoke trails from said airplanes, and controlling the timing, length and placement of the smoke trails by signals to the several airplanes, which signals are amplied and rendered perceptible to the pilot and serve to guide him in operating smoke trail releasing mechanism, said smoke trails cooperating to form individual and successive letters or symbols.

4. The method for forming letters or symbols in the air by means of smoke trails, comprising the steps of assigning to each of a plurality of airplanes a certain part of each letter or symbol, flying said airplanes in contiguous and substantially parallel paths, releasing substantially parallel smoke trails from said airplanes, and controlling the timing, length and placement of the smoke trails by signals to the several airplanes, amplifying such signals and causing such amplilied signals to control directly mechanism for releasing smoke trails of controlled length at controlled intervals, said smoke trails cooperating to form individual and successive letters or symbols.

5. The method for forming letters or symbols in the air by means of smoke trails, comprising the steps of assigning to each of a plurality of airplanes a certain part of each letter or symbol, flying said airplanes in contiguous and substantially parallel paths, releasing substantially parallel smoke trails from said airplanes, and controlling the timing, length and placement of the smoke trails by sending signals to the several airplanes, such signals involving the use of one of the following: sound Waves, invisible light waves; the timing and duration of such waves determining the placement and length of the smoke trails, said smoke trails cooperating to form individual and successive letters or symbols.

6. Apparatus for forming letters or symbols in the air by means of smoke trails, comprising a plurality of airplanes arranged to fly in substantially parallel paths, each provided With mechanism for forming smoke trails, valve mechanism in each airplane for controlling the release of such smoke trails, and wave receiving and amplifying means for use in controlling said valve mechanism, for determining the placement and length of the smoke trails in accordance With the timing and duration of the received Wave, said smoke trails being substantially. parallel and cooperating to form individual and successive letters or symbols.

7. Apparatus for forming letters or symbols in the air by means of smoke trails, comprising a plurality of airplanes arranged to fly in substantially parallel paths, each provided with mechanism for forming smoke trails, valve mechanisin in each airplane for controlling the release of such smoke trails, and Wave receiving and amplifying means for directly controlling said valve mechanism, for determining the placement and length of the smoke trails in accordance with the timing and duration of the received Wave, said smoke trails being substantially parallel and cooperating to form individual and successive letters or symbols.

18., Apparatus for forming letters or symbols in the air by means of parallel smoke trails, comprising smoke trail releasing mechanism, means for receiving a signal of a predetermined wave length, and means for amplifying such received signal and operating the smoke trail releasing mechanism for controlling the formation of the smoke trail in accordance with the timing and duration of the received signal.

9. Apparatus for use in forming letters or symbols in the air by means of smoke trails, wherein a plurality of signal Waves of different wavelengths are selectively received by a corresponding plurality of airplanes flying in parallel paths, comprising means for generating a plurality of signals of different Wave lengths, means for controlling the timing and duration of such signals, comprising a travelling record, plural pick-up members, each allocated to cooperate With a particular longitudinal zone on the record and actu'- ated by indicia carried by the record, the several pick-up members respectively controlling the formation of different parts of the saine letter, said pick-up members being individually and operatively connected to said signal generating means, and signal Wave receiving means in each of said airplanes, each of which is responsive to only one particular wave length as generated by said signal generating means.

l0. Apparatus for use in forming letters or symbols in the air by means. of smoke trails, wherein a plurality of signal waves of diierent wave lengths are selectively received by a corresponding plurality of airplanes iiying in parallel paths, comprising means for generating a plurality of signals of dierent Wave lengths, and means for controlling the timing and duration of such signals, comprising a travelling record, said record being provided with indicia in the form of longitudinal slots, a plurality of contact closing brushes allocated to cooperate with particular slots in the record, each of said brushes, and its corresponding slot, respectively controlling the formation of different parts of the same letter, said contact closing brushes being respectively connected to the signal generating means, Whereby signals of different Wave lengths are sent out, the timing and duration of which correspond to the position and length of the corresponding slot in the record, and signal Wave receiving means in each of said airplanes, each of which is responsive to only one particular Wave length as generated by said signal generating means.

l1. Apparatus for use in forming letters or symbols in the air by means of smoke trails, comprising a plurality of airplanes arranged to ily in substantially parallel paths, smoke trail releasing mechanism carried by each airplane, for forming predetermined parts of a letter or symbol and selective signal receiving means carried in each airplane, for use in controlling the timingv and duration of the operation of the smoke trail releasing mechanism in such airplane, said smoketrails being substantially parallel and cooperating to form individual and successive letters or symbols, and signal generating means for generating signals for individual reception b-y said signal receiving means in the several airplanes, said smoketrails being substantially parallel and cooperating to form individual and successive letters or symbols.

l2. Apparatus for use in forming letters or symbols in the air by means of smoke trails, comprising a plurality of airplanes arranged to y 'in substantially parallel paths, smoke trail releasing mechanism carried by each airplane, for forming predetermined parts of a letter or symbol selective signal receiving means carried in each airplane, and means in each airplane for amplifying such received signal and directly operating the corresponding smoke trail releasing mechanism, for controlling the timing and duration of the smoke trail made by that airplane, said smoketrails being substantially parallel and cooperating to form individual and successive letters or symbols, and signal generating means for generating signals for individual reception by said signal receiving means in the several airplanes, said smoketrails being substantially parallel and cooperating to form individual and successive letters or symbols.

13. Apparatus for use in forming letters or symbols in the air by means of smoke trails, cornprising a plurality of airplanes arranged to ily in substantially parallel paths, smoke trail releasing mechanism carried by each airplane, for forming predetermined parts of a letter or symbol selective signal receiving means carried in each airplane, for use in controlling the timing and duration of the operation of the smoke trail releasing mechanism in such airplane and means for sending signals of diierent wave lengths at controlled intervals to the several airplanes, for selective reception thereby, said smoketrails being substantially parallel and cooperating to form individual and successive letters or symbols, and signal generating means for generating signals for individual reception by said signal receiving means in the several airplanes, said smoketrails being substantially parallel and cooperating to form individual and successive letters or symbols.

14. Apparatus for use in forming letters or symbols in the air by means of smoke trails, comprising a plurality of airplanes arranged to ily in substantially parallel paths, smoke trail releasing mechanism carried by each airplane, for forming predetermined parts of a letter or symbol, selective signal receiving means carried in each airplane, means in each airplane for amplifying such received signal and directly operating the corresponding smoke trail releasing mechanism, for controlling the timing and duration of the smoke trail made by that airplane and means for sending signals of different wave lengths at controlled intervals to the several airplanes, for selective reception thereby, said sm-oketrails being substantially parallel and cooperating to form individual and successive letters or symbols, and signal generating means for generating signals for individual reception by said signal receiving means in the several airplanes, said smoketrails being substantially parallel and cooperating to form individual and successive letters or symbols.

15. The method for forming letters or symbols in the air by means of smoke trails, comprising the steps of assigning to each of a plurality of airplanes a certain part of each letter or symbol, ilying said airplanes in contiguous and substantially parallel paths, intermittently releasing substantially parallel smoke trails from said airplanes, the length, timing and placement of the smoke trails being determined by plural signals selectively received by the individual airplanes, said smoke trails cooperating to form individual and successive letters or symbols.

16. The method for forming letters or symbols in the air by means of smoke trails, comprising the steps of assigning to each of a plurality of airplanes a certain part of each letter or symbol, flying said airplanes in contiguous and substantially parallel paths, intermittently releasing substantially parallel smoke trails from said airplanes, the length, timing and placement of the smoke trails being determined by plural signals of diiTerent Wave lengths selectively received by the several airplanes, said signals being amplified and serving to operate smoke trail releasing mechanism, said smoke trails cooperating to form individual and successive letters or symbols.

1'7. The method for forming letters or symbols in the air by means of smoke trails, comprising the steps of assigning to each of a plurality of airplanes a certain part of each letter or symbol, ilying said airplanes in contiguous and substantially parallel paths, intermittently releasing substantially parallel smoke trails from said airplanes, the length, timing and placement of the smoke trails being determined by plural signals of diierent wave lengths selectively received by the several airplanes, said signals being amplified and rendered perceptible to the operator and serving to guide him in controlling smoke trail releasing mechanism, said smoke trails cooperating to form individual and successive letters Vor symbols.

18. The method of forming letters or symbols in the air, comprising the steps of assigning to each of a plurality or airplanes a certain part of each letter or symbol, ilying said airplanes in substantially parallel paths, and releasing parallel smoke trails of controlled length at controlled intervals, from the several airplanes, for building up individual and successive letters or symbols by use of such parallel trails.

JOHN T. REMEY. 

